Although the function of the corneal epithelium in normal and diseased states has been extensively studied, there has been little investigation of the functional properties of the conjunctival epithelium. This project will examine and analyze the functions of the conjunctiva in various normal and pathologic conditions, utilizing cytochemical methods for transmission electron microscopy. We will expose the conjuntivas of normal anesthetized guinea pigs to soluble tracer substances such as horseradish peroxidase and cationized ferritin, and then apply cytochemical methods to probe the cellular events of pinocytosis and digestion. Other experiments will analyze digestion in the eyes of guinea pigs infected with Listeria monocytogenes and guinea pig inclusion conjunctivitis, a Chlamydia psittaci infection. Lastly, experiments will be carried out to determine whether the normal functions of pinocytosis and digestion are altered in GPIC. Specific experiments will include: - Examining the uptake of soluble exogenous substances (horseradish peroxidase and ferritin), and identification of the host cell response by cytochemical methods to identify the lysosomal enzymes, aryl sulfatase and acid phosphatase. - Analyzing phagocytosis and digestion of Staphylococcus aureus and latex particles by the conjunctival epithelium. - An assessment of the intracellular response to invading Listeria monocytogenes by demonstrating the intracellular distribution of lysosomal enzymes. - Localizing the digestive enzymes in the conjunctival epithelium of guinea pigs infected with guinea pig inclusion conjunctivitis. - Analysis of the uptake and fate of tracer substances in the conjunctivas of guinea pigs affected with GPIC. These experiments will elucidate how exogenous substances and microbial agents are treated by the conjunctival epithelial cells in terms of simple transport or degradation within lysosomes. The response of the conjunctival epithelium during acute infections will provide information on functional abnormalities induced in these cells as a consequence of the infections.